Method and installation for cooling slaughtered poultry

ABSTRACT

The invention relates to a method for cooling slaughtered poultry, including the steps of: positioning the poultry with spread legs, with the abdominal cavity upward and oriented in the transporting direction of the poultry; and transporting the positioned poultry through cooled flowing water, wherein the transporting direction of the poultry is opposed to the flow direction of the water such that water flows around and through the poultry from the abdominal cavity toward the neck cavity. The present invention also relates to an installation including: positioning means for receiving the slaughtered poultry with the abdominal cavity oriented upward in the transporting direction; transporting means for transporting the positioned poultry; and cooling means comprising a container for cooled and flowing water, wherein the flow direction is opposed to the transporting direction, and to the treated poultry.

[0001] The present invention relates to a method and installation forcooling slaughtered poultry.

[0002] When poultry are slaughtered, legs, neck, feathers and entrailsare removed. The slaughtered poultry then has to be cooled. Cooling withair has the drawback that it takes place over a long period of time andthe slaughtered poultry acquires grey-yellow colour with dark blotches.In addition, there occurs a weight loss (up to 3%).

[0003] According to another known method, slaughtered poultry isdisplaced in a screw spindle in counterflow to water. Because thepoultry birds lie against each other in the spindle they are mangled,whereby insufficient cooling occurs and cooling must continue for a longperiod before a desired temperature of below +4° C. is reached. Inaddition, the amount of water used is considerable.

[0004] The present invention has for its object to provide a method andinstallation for cooling slaughtered poultry, wherein cooling takesplace very rapidly. The slaughtered poultry hereby retains a healthycolour, has a long storage time and there occurs substantially no weightloss. This cooling can take place by making use of only cooled flowingwater, while the use of chemicals in whatever form can be dispensedwith.

[0005] The present invention is based on the insight that theeffectiveness of the cooling is enhanced not only by external cooling ofthe poultry but also by simultaneous internal cooling of the poultry,this while each poultry bird is subjected separately to the cooling.Vasoconstriction is enhanced because the breastbone is herein preventedfrom being pressed inward and by the rapid cooling, whereby no weightloss of the slaughtered poultry occurs during the cooling and the weightof the slaughtered poultry therefore remains substantially the same asthe slaughtered weight. It will be apparent that any contamination whichmay be present on the poultry is also effectively removed by this methodof cooling according to the invention. This results in a considerabledecrease in the germ value.

[0006] The invention therefore provides a method for cooling slaughteredpoultry, comprising of:

[0007] i. positioning the poultry with spread legs, with the abdominalcavity upward and oriented in the transporting direction of the poultry;and

[0008] ii. transporting the positioned poultry through cooled flowingwater, wherein the transporting direction of the poultry is opposed tothe flow direction of the water such that water flows round and throughthe poultry from the abdominal cavity toward the neck cavity. For theinternal circulation and cooling of the slaughtered poultry it isimportant that the legs of the poultry be spread and the abdominalcavity be oriented upward in the transporting direction. Due to theopposed directions of the transporting direction of the poultry and theflow direction of the cooling water there occurs a thrust at theposition of the open abdominal cavity of the poultry. Water will therebypass from the abdominal cavity through the slaughtered poultry and leavethe poultry via the neck cavity. According to a first embodiment theside of the body is oriented in the transporting direction. According toa second preferred embodiment the rear of the body is oriented in thetransporting direction. Because the rear of the body is oriented in thetransporting direction, the breastbone will not be pressed inward by thethrust of the water, so that flow through the poultry from abdominalcavity to neck cavity can take place.

[0009] Poultry is understood to means all kinds of fowl, includingchickens such as maternal animals, chicks and laying-hens, ducks,pheasants, guinea fowl, geese, turkeys and the like.

[0010] After cooling of the slaughtered poultry, further cooling cantake place to the temperature for further processing. In order to avoidas far as possible any fouling of the cooling water, it is furtherrecommended that the cooled poultry be allowed to drain. The chicken canthus drain and fouled water possibly present thereon can be removedprior to further cooling. It is therefore recommended that the poultryis then further cooled.

[0011] If the poultry is intended for the fresh-food market, it isrecommended that the further cooled poultry is subjected to air coolingto below as from +4° C.

[0012] If the poultry is intended in particular for the frozen foodmarket, it is recommended that the further cooled poultry isdeep-frozen.

[0013] Another aspect of the invention relates to an installation forperforming the above stated method. This installation comprises:

[0014] i. positioning means for receiving the slaughtered poultry withthe abdominal cavity oriented upward in the transporting direction;

[0015] ii. transporting means for transporting the positioned poultry;and

[0016] iii. cooling means comprising an elongate container for cooledand flowing water, wherein the flow direction is opposed to thetransporting direction.

[0017] The poultry can be oriented with the side of the body of the rearof the body in the transporting direction.

[0018] As stated above, it is further recommended that the positioningmeans comprise receiving members for receiving the legs of the poultryin spread manner. An elegant positioning is obtained if in furtherpreference the receiving members comprise slots oriented in thetransporting direction in which a poultry leg is hookingly received. Itis hereby possible to arrange the poultry manually or automatically inthe positioning means and to remove them easily therefrom after cooling.If placing of the poultry or removal of the poultry takes place in adirection transversely of the transporting direction, it is furtherrecommended that the positioning means are connected via a rotatableframe to the transporting means. It is thus possible to carry out atransverse arranging or removing operation after rotation.

[0019] For the above stated reasons it is further recommended that theinstallation further comprises a draining station connecting onto thecooling container, and optionally a further cooling means which connectsonto the draining station and comprises a further cooling container forcooled and flowing water, wherein the flow direction is opposed to thetransporting direction.

[0020] Owing to the rapid cooling of the slaughtered poultry the poultryretains a healthy white colour, and has a shelf-life for the fresh-foodmarket of at least eight days. While gray colours and dark or rustpatches practically do not occur. The cooling operation performedthereon in accordance with the method and installation according to theinvention is therefore characteristically visible on the slaughteredpoultry. Another feature of the poultry is that the slaughtered weightis substantially the same as the cooled weight. The uniform, white andnatural colour of the slaughtered poultry depends partly on the type ofpoultry and the poultry diet. It can be generally stated that thepoultry obtained according to the invention has a uniform naturalcolour, such as RAL 9010 or 9003 for maternal animals and chicks, andRAL 9001 or 1013 for laying-hens.

[0021] Mentioned and other features of the method and installation aswell as the slaughtered poultry according to the invention will befurther elucidated hereinbelow on the basis of an embodiment, which isgiven only by way of example without the invention being deemed limitedthereto. Reference is made herein to the annexed drawing, in which:

[0022]FIG. 1 is a schematic perspective view of the installationaccording to the invention;

[0023]FIG. 2 shows on a larger scale a broken-away view of detail II ofFIG. 1;

[0024]FIG. 3 shows on a different scale the removal operation at theposition of detail III in FIG. 1; and

[0025]FIGS. 4 and 5 each show another variant of the installationaccording to the invention.

[0026]FIG. 1 shows an installation 1 for cooling slaughtered poultry 2,in this case chickens. Installation 1 comprises a transport system 3which passes through a hairpin bend-like cooling container 4, thenthrough a draining station 5 and a further cooling container 6. From thestation 7 the transport system 3 once again connects onto coolingcontainer 4 in a manner not shown.

[0027] Cooling container 4 and further cooling container 6 aremanufactured from stainless steel. Both containers lie at an inclinationsuch that the transporting direction 8 in cooling container 4 and thetransporting direction 9 in further cooling container 6 is opposed tothe water flow direction 10 respectively 11 in cooling container 4 orfurther cooling container 6. The speed of the transport system and thelength of cooling container 4 and further cooling container 6 anddraining station 5 are chosen such that the chickens 2 remain for about2-3 minutes in cooling container 4, drain for 3 minutes in drainingstation 5 and are in further cooling container 6 for about 7 minutes,when air cooling to the desired final temperature of for instance 4° C.is subsequently reached, or further cooling with the same system untilthe desired final temperature is reached (of for instance 4° C.).

[0028] The cooling water in cooling container 4 and in further coolingcontainer 6 can be cooled via cooling means (not shown) or can beprovided with ice in order to obtain a temperature below 4° C.

[0029]FIG. 2 shows the further cooling of chickens 2 in more detail.

[0030] Transport system 3 comprises a transport rail 12 along which atransport frame 14 passes via wheels 13. Transport frames 14 aremutually connected via a link 15.

[0031] Each transport frame 14 is provided with an eye 15 in which ashaft 16 of positioning means 17 is rotatably received. Shaft 16 ends ina stop 18 which, during transport as according to arrow 9 in FIG. 2,presses against a stop 19. In this position the receiving members 20 areoriented in the transporting direction, wherein open slots 20, hookingon the knee joint 21, receive legs 22 of chicken 2 in this direction 9.In this position the legs 22 are hookingly received in slots 20 inspread manner. Abdominal cavity 23 is oriented upward and neck cavity 24is oriented downward. The rear of the body 25 is oriented in thetransporting direction 9 and counter to the water flow direction 11. Thefront of the body 26 with the breastbone is oriented in the otherdirection. Owing to the displacement of chicken 2 counter to the flowdirection 11, water 27 flows round the chicken 2 at the sides and thechicken is cleaned and cooled on the outside with water 28. Owing to thethrust of water at the position of the abdominal cavity 23, whichcommunicates with neck cavity 24 via the interior of chicken 2, aninternal flow of water 29 is created whereby chicken 2 is also cooledinternally.

[0032] The further cooling container 6 is manufactured from stainlesssteel and is provided with baffles 30 which guide settling dirt whichmay be present toward the middle of container 6. Located here is an airpipe 32 with downward directed holes 32 through which air is blown, sothat air bubbles 33 cause an agitation and swirling in the water 28.This enhances cooling.

[0033] Although the operation of only the further cooling container 6 isdescribed in detail in FIG. 2, it will be apparent that the same coolingprocess takes place in cooling container 4, which has the sameconstruction but has a shorter length because of the shorterpost-cleaning and cooling operations performed therein.

[0034] In draining station 5 the chicken 2 passes through suspended fromthe slots 20 of receiving members 19, while water, which is collected ina tank (not shown) can drain away from the outside and inside. Thechicken 2 suspended from the transport system 3 is herein situated incool air so that warming of the chicken is avoided.

[0035]FIG. 3 shows the transfer of chicken 2 from the transport system3. Using a stop guide 34 the stop 18 is rotated in the direction ofarrow 35 and strikes against a stop 36. The slots 20, with the legs 22of chicken 2 therein, are hereby rotated and displaced, in this casecounter-clockwise, in a direction transversely of transporting direction9. Chicken 2 can hereby be taken out of slots 20 transversely of thetransporting direction 9 and transferred into another transport systemwhich feeds the chickens for instance to a device for dividing chicken2. It is also possible for the chicken to be fed to a device forperforming an air cooling of the further cooled chickens 2, or to adevice for deep-freezing chickens 2, this depending on the further useof the chicken for the fresh-food market or the frozen-food market.

[0036]FIG. 4 shows a variant corresponding with FIG. 2 of the transportsystem 3. Each transport frame 14 comprises a cradle 37 which isconnected to a transport rod 39 for pivoting on a pin 38.

[0037] Each cradle 37 is provided with receiving members 40 forhookingly receiving the knee joint 21 of a chicken 2. The abdominalcavity 23 is oriented upward and the neck cavity 24 oriented downward.The side of the body 41 is oriented in the transporting direction 9 andcounter to the water flow direction 11. Water 27 flows round the sidesof chicken 2. The thrust of water at the position of the side of thebody 41 results in an internal flow of water 29 whereby chicken 2 iscooled internally. Owing to the thrust and tilting of cradle 37 roundpin 38 the abdominal cavity 23 will be oriented in the direction of thewater flow 29, thereby ensuring a good internal flow.

[0038]FIG. 5 shows a variant of the transport system 3 shown in FIG. 4.In this case the cradle 37 is rigidly connected to rod 39, wherebyduring transport through the cooling containers the abdominal cavity 23is not oriented in the direction of the water flow 29. An adequateinternal cooling of chicken 2 is nevertheless ensured.

[0039] After the air cooling, deep-freeze cooling and/or packaging thechicken 2 possesses a natural, uniform colour and is substantially freeof dark blotches and yellow discoloured patches. This is obtained due tothe rapid cooling. Moisture loss is prevented by the vasoconstrictionoccurring herein. The weight loss relative to the slaughtered weight iseven zero in many cases. The colour of the cooled chicken according tothe invention has a natural slaughter colour. For maternal animals, hensand chicks this colour can be the same in many cases as that of RAL 9010or 9003. For laying-hens the colour usually corresponds with RAL 9001and 1013. It is however noted that, depending on diet, the colour of thechicken can vary, and also as a result of differences in breed. Itremains important however that unnatural discolouration and darkcolouring are avoided by the invention owing to the efficient cooling.

1. Method for cooling slaughtered poultry, comprising of: i. positioningthe poultry with spread legs, with the abdominal cavity upward andoriented in the transporting direction of the poultry; and ii.transporting the positioned poultry through cooled flowing water,wherein the transporting direction of the poultry is opposed to the flowdirection of the water such that water flows round and through thepoultry from the abdominal cavity toward the neck cavity.
 2. Method asclaimed in claim 1, wherein the side of the body is oriented in thetransporting direction.
 3. Method as claimed in claim 1, wherein therear of the body is oriented in the transporting direction.
 4. Method asclaimed in claims 1-3, wherein the cooled poultry is allowed to drain.5. Method as claimed in claims 1-4, wherein the cooled and cleanedpoultry is further cooled.
 6. Method as claimed in claim 5, wherein thefurther cooled poultry is subjected to air cooling to a desired finaltemperature below as from +4° C.
 7. Method as claimed in claim 5,wherein the further cooled poultry is deep-frozen.
 8. Installation forcooling slaughtered poultry, comprising: i. positioning means forreceiving the slaughtered poultry with the abdominal cavity orientedupward in the transporting direction; ii. transporting means fortransporting the positioned poultry; and iii. cooling means comprising acontainer for cooled and flowing water, wherein the flow direction isopposed to the transporting direction.
 9. Installation as claimed inclaim 8, wherein the positioning means orient the poultry with the sideof the body in the transporting direction.
 10. Installation as claimedin claim 8, wherein the positioning means orient the poultry with therear of the body in the transporting direction.
 11. Installation asclaimed in claims 8-10, wherein the positioning means comprise receivingmembers for receiving the legs of the poultry in spread manner. 12.Installation as claimed in claim 11, wherein the receiving memberscomprise slots oriented in the transporting direction in which a poultryleg is hookingly received.
 13. Installation as claimed in claims 8-12,wherein the positioning means are connected via a rotatable frame to thetransporting means.
 14. Installation as claimed in claims 8-13,comprising a draining station connecting onto the cooling container. 15.Installation as claimed in claim 14, comprising a further cooling meanswhich connects onto the draining station and comprises a further coolingcontainer for cooled and flowing water, wherein the flow direction isopposed to the transporting direction.
 16. Slaughtered poultryobtainable according to the method as claimed in claims 1-7 or theinstallation as claimed in claims 8-15.
 17. Poultry as claimed in claim16, wherein the slaughtered weight is substantially the same as thecooled weight.
 18. Poultry as claimed in claim 16 or 17, with a uniformnatural colour, such as RAL 9010 or 9003 for maternal animals andchicks, and RAL 9001 or 1013 for laying-hens.